Why is it that WWE pay per views always end like 15 minutes early and RAW always ends like 10 minutes late?

WWE times the Pay Per Views to give Advertising Time for The Replays and other Pay Per Views. WWE and Comcast-NBC/Universal deliberately let WWE Monday Night Raw run past 11:00 PM Eastern Time for additional Ratings.

When WWE times out the show, they always time it out and leave about 15-20 minutes to spare so that if they need to add something else they won't have the problem of going off air. 15 minutes gives WWE a comfortable cushion. If they have nothing to add they'll just end it early

Because USA has given them permission to go over time where as the company that hosts the PPV will cut them off if they go over a certain time.